This invention relates to transport mechanisms for moving test samples to and from a test station in systems for measurement and recording of sample properties, such as radioactivity, light transmissivity or fluorescene, or for sample preparation in diagnostic testing prior to such measurements. More particularly, it relates to test sample transport systems which depend upon levers as opposed to chains or conveyors to move the samples to test stations.
Conventional sample transport mechanisms for the above purposes, have been known and utilized for many years. The predominant characteristics of such transports have been the use of chains and sprockets in a serpentine configuration, or other endless chain-type conveyors in another configuration. These may be seen in applications either for carrying discrete samples, or for driving trays supporting a set number of samples in a predetermined path. The degree of complexity of such conventional sample transports, the consequent expense of both manufacture and maintenance, and the inherent reliability problem have long been recognized as disadvantages which it would be desirable to obviate.
It has been attempted to obviate these disadvantages through various modifications involving cams, levers and guides, but it has been found that no great degree of simiplification has actually been obtained. Rather, problems have been merely transferred to other areas of the mechanism. Moveover, it has been found that such prior designs have been primarily amenable to transport of either trays or discrete samples, but not both.